Henry



PATENT OFFICE.

HENRY LS. YACKERLY, OF NEV YORK, N. Y.

PIANOFORTE-FRAME.

ESpeccaton of LettersPatentNo. 12,432, dated February 27, 1855.

To all whom t may concern.'

Be it :known that I, HENRY S. ACKERLY, of the city, county, and `Stateof ANew York, have invented a new and useful Improvement inPianofortesj; and I do hereby declare that Athe following is a full,clear, and exact description of the same, reference Abeing had to theaccompanying drawings, forming part of this specification, in which-Figure l, is a plan view of my invention. Fig. 2, an end view from theright hand of Fig. l. Fig. 3, is a section in the line m, y, of Fig. 1,looking in the direction of the arrow.

Similar letters of reference indicate corresponding parts in the severalfigures.

This invention relates to a certain arrangement of the wrest plank ortuning block and the strings of a square pianoforte for the purpose ofenabling the strings to be carried and sustained by a metallic framewhich is independent of the case, and the case to be relieved of theirstrain, and the power and durability of the instrument to be increasedwithout enlarging it. 1

It further relates to the peculiar construction of the metallic framefor the above purose.

To enable those skilled in the art to make and use my invention I will'proceed to describe its construction andoperation.

A, is the wrest plank or tuning block; B, B, B, is the cast iron frame;a, a, and t, b, are the strings. The wrest plank instead of being placedat the back of the instrument as is usual in the square pianoforteextends partly along the front and diagonally across the front left handcorner, the diagonal part c, being more elevated than the part d, whichextends straight along the front, for the purpose of allowing thestrings to be arranged in two tiers, of which the upper tier a, a,connected with the part c, of the wrest plank comprises the longeststrings, and the lower tier b, b, connected with the part al, of thewrest plank comprises the shorter strings. The strings a, a, run nearlyparallelwith the front and back of the case, and those b, b, diagonallyacross. In this way I obtain the greatest length of string for the loweroctaves that can be obtained in a square piano-forte.

The plate B, which may be generally of cast iron is made to fit in andfill the entire horizontal section of the interior of the case, and isto be of such thickness as may be found jnecessary to sustain fthetensionlof the strings, but in order 4so `to distribute ithe metal so:as to obtain the greatest 4strength Vfrom the lea-st weight fmake astout brace e, at the back part parallel with land lying =close to theback -of fthe plate :and from 'thc ends of this Abrace fe, carry an archlf, to `the .front of ithe plate. The arch f, is :raised above the solidpart of the -plate sin .the form of a moulding, but the brace e, standsalone. The straight brace e, gives thrust to sustain the tension of thelong strings and corresponds in its e'tl'ect with the brace now used.The arch f, sustains the tension of the short strings. That part of theplate which receives the hitch pins occupies nearly the same position asthe metallic plate commonly used, and the hitch pins of the shortstrings are placed near its edge, in the usual Inanner, but the hitchpins of the long strings are in a raised part g, near the end. The

plate rests on a suitable ledge all round or at suitable parts of theinterior of the case. The wrest plank drops int-o a recess made ofnearly or quite its full depth to receive it, said recess being includedbetween the arch f, and the raised rib L, through which holes aredrilled for the strings to pass. The rib lz, sustains the plank againstthe tension of the strings, but the plank is secured by screws passingthrough the plate in order to keep it down solidly on its resting placeon the plate. By placing the wrest plank above the plate B, as describedI disconnect the strings as far as possible from the plate and therebypreserve their tone better, but I do not wish to confine myself toplacing the wrest plank above the plate as it may be covered by theplate, like it has heretofore been when the full metallic plate as it istermed has been used.

The reason for arranging the wrest plank in the front of the instrumentas described instead of in the usual position, is that in the usualposition the plate would require to be extended farther back to give itstrength to hold the wrest plank and would make the case larger thanusual; but by arranging the wrest plank as described, it is made tooccupy a space which would otherwise be useless and the case does notrequire to be made above the usual size. Another advantage also resultsfrom the within described arrangement of the wrest plank and strings,viz, the shortest key is brought oppOSte the shortest string, and thelongest What do claim as my invention and desire to secure by LettersPatent isl. The arrangement of the Wrest plank of a square piano-fortealong the front and across one of the front corners of the instrument asdescribed, to receive two tiers of strings of Which the tier comprisingthe longest strings is arranged nearly parallel With the front and backof the instrument and the shorter ones diagonally across the same, saidarrangement being for the purpose herein fully set forth.

2. The construction of the metallic plate B, B, with the straight bracec, across the back and t-he arched molding or brace f, running from thesaid straight brace to the front of the instrument as and for thepurpose herein set forth.

3. Constructing the plate B, B7 with a recess to receive the Wrest plankso that it may be firmly secured against the tension of the stringssubstantially as herein set forth.

HENRY S. ACKERLY.

Vitnesses:

S. H. WALLS, I I. G. MASON.

